The International Bone Fluid Flow Workshop started six years ago in New York and has been held annually. Bone fluid flow research has become a promising area for various bone related hot topics, e.g., the response to fluid flow on the tissue level as well as the cellular and molecular levels, its role in tissue engineering, and its therapeutic potential for bone disease. Previous IBFF workshops provided a successful forum for the discussion of fluid flow effects in bone related health problems. These workshops have greatly impacted our understanding of the role of fluid flow in cellular and tissue mechanotransduction. Our upcoming IBFF meeting will be held in Seattle, WA, Sept. 30 - Oct. 1, 2004. The current workshop is designed to provide a disciplinary forum at this exciting stage for the current and future research directions, in which the field of bone fluid flow is on the cusp of exploring the mechanism for fluid flow on cellular activities, bone fluid flow imaging, and translation to the clinic. The goals of this Bone Fluid Flow Workshop are to stimulate a disciplinary program for a disciplinary audience including bone biologists, engineers and clinicians. This will be achieved in fivefold. First, recent breakthroughs in fundamental pathways related to fluid flow through bone will be presented. Second, newly developed experimental and imaging approaches to measure fluid flow through bone will be presented. Third, cellular and molecular mechanotransduction and tissue engineering aspects in bone fluid flow will be discussed. Fourth, critical issues of the physiological mechanism and translation of clinical research related to fluid flow through bone will be identified and presented. Fifth, promotion of graduate students and young investigators will be emphasized. A web site has been created for information, abstract submission, and registration, as well as other necessary communication. The site is hosted in Stony Brook University in an address of http://bme.sunysb.edu/Bone- Fluid-Flow/. An exciting program with scientific sessions is planned. 1. Fundamental biology and engineering aspects of fluid flow pathways in bone 2. Imaging and experimental approaches for fluid flow through bone 3. Cellular and Molecular Response to Fluid Flow Stimulation 4. The role of fluid flow in tissue engineering 5. Physiological mechanism and clinical implications of bone fluid flow.